Lens for a camera provided with code patterns

Abstract

A lens information introducing device in a camera comprises n bits of code patterns provided on a lens and photoelectrically legible, optical means for introducing the code patterns into a camera body and imaging the same at a predetermined position, and photoelectric converter means disposed at the predetermined position and having n photoelectric converting elements corresponding to the code patterns and being effective to produce a digital electrical signal corresponding to the lens information on the basis of the photoelectric signals produced by the photoelectric converting elements.

I claim: 
     
       1. A lens information introducing device in a camera, comprising: n bits of code patterns provided on a lens, said patterns being photoelectrically legible;   optical means for introducing said code patterns into a camera body and imaging the same at a predetermined position; and   photoelectric converter means disposed at said predetermined position, said photoelectric converter means having n photoelectric converting elements corresponding to said code patterns and being effective to produce a digital electrical signal corresponding to the lens information on the basis of the photoelectric signals produced by said photoelectric converting elements.   
     
     
       2. The device according to claim 1, wherein said n bits of code patterns are provided on the outer surface of the lens. 
     
     
       3. The device according to claim 2, wherein said n bits of code patterns are provided on a movable member such as an aperture ring, a distance ring or the like and the imaging pattern by said optical means is varied by displacement of said movable member. 
     
     
       4. The device according to claim 3, wherein said n bits of code patterns are light and dark stripes. 
     
     
       5. The device according to claim 4, wherein said n bits of code patterns are one track of patterns comprising binary codes of M-sequences or improved M-sequences. 
     
     
       6. The device according to claim 3, wherein said n bits of code patterns are numerical patterns. 
     
     
       7. The device according to claim 4 or 5 or 6, wherein said photoelectric converter means has comparing means for comparing the output signals of said photoelectric converting elements with a signal of a predetermined level and generating one of two values in accordance with the magnitudes of said signals, and produces said digital electrical signal as the output of said comparing means. 
     
     
       8. The device according to claim 1, wherein the lens is removably mountable with respect to the camera body. 
     
     
       9. A lens for use with a camera body having an optical system for imaging a predetermined position of the outer peripheral portion of the lens within the camera body, and a processing device for reading the lens information by a signal from photoelectric converter means provided at the image forming position of said optical system, said lens including; n bits of code patterns provided at the predetermined position of the outer peripheral portion of the lens, said patterns representing the lens information.   
     
     
       10. The lens according to claim 9, wherein said n bits of code patterns are provided on a movable member such as an aperture ring, a distance ring or the like, and said code patterns lying at said predermined position are varied by displacement of said movable member. 
     
     
       11. The lens according to claim 10, wherein said n bits of code patterns are light and dark stripes. 
     
     
       12. The lens according to claim 11, wherein said n bits of code patterns are one track of patterns comprising binary codes of M-sequences or improved M-sequences. 
     
     
       13. The lens according to claim 12, further having a mount portion to enable the lens to be removably mounted to the camera body. 
     
     
       14. A device for reading code patterns in a camera using a lens provided with lens information as n bits of code patterns, said device including; optical means for introducing said code patterns into a camera body and imaging the same at a predetermined position; and   photoelectric converter means disposed at said predetermined position, said photoelectric converter means having n photoelectric converting elements corresponding to said code patterns and being effective to produce a digital electrical signal corresponding to the lens information on the basis of the photoelectric conversion signals from said photoelectric converting elements.   
     
     
       15. The device according to claim 14, wherein said photoelectric converter means has comparing means for comparing the output signals of said photoelectric converting elements with a signal of a predetermined level and producing one of two values in accordance with the magnitudes of said signals, and generate said digital electrical signal as the output of said comparing means.